KVM: s390: vsie: Fix refcount overflow for shadow gmaps

In most cases gmap_put() was not called when it should have.

Add the missing gmap_put() in vsie_run().

Fixes: e38c884df921 ("KVM: s390: Switch to new gmap")
Reviewed-by: Steffen Eiden <seiden@linux.ibm.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>

diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c
index 0330829b4046cd9d15ea933cab9121ab713ff5bf..72895dddc39afa19b3f184a03efbc04c60b5501f 100644 (file)
--- a/arch/s390/kvm/vsie.c
+++ b/arch/s390/kvm/vsie.c
@@ -1328,7 +1328,7 @@ static void unregister_shadow_scb(struct kvm_vcpu *vcpu)
 static int vsie_run(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
 {
        struct kvm_s390_sie_block *scb_s = &vsie_page->scb_s;
-       struct gmap *sg;
+       struct gmap *sg = NULL;
        int rc = 0;
 
        while (1) {
@@ -1368,6 +1368,8 @@ static int vsie_run(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
                        sg = gmap_put(sg);
                cond_resched();
        }
+       if (sg)
+               sg = gmap_put(sg);
 
        if (rc == -EFAULT) {
                /*